This invention relates generally to lenticular filters for displaly devices and particularly to such a filter which filters both the horizontal and vertical lines of such a display device.
The use of lenticular filters to eliminate undesirable lines in display devices is well documented in the prior art. U.S. Pat. No. 2,728,013 shows a lenticular filter being used to eliminate the horizontal scan lines in a kinescope. Also, the use of a lenticular filter to suppress the vertical phosphor line structure of a color television picture tube is described by A. M. Morrell in a publication entitled "Color Television Picture Tubes--Supplement 1--Advances in Image Pickup and Display" published by Academic Press in 1974 and described at pages 170 and 171 of a book entitled "Image Pickup and Display". Thus, the prior art shows the use of lenticular filters to suppress either horizontal lines or vertical lines, depending upon the orientation of the lenticular filter with respect to the display screen. However, some display devices, such as large kinescopes, liquid crystal displays or guided beam flat displays typically have undesirable lines in both the horizontal and vertical directions. For this reason, there is a need for a device for suppressing the undesirable lines in both directions. The present invention fulfills this need.